Prognostic value of the metabolic syndrome in essential hypertension

Abstract

Objectives: We sought to determine the prognostic significance of the metabolic syndrome in hypertension.

Background: Increased cardiovascular risk in hypertensive patients might be partially attributable to metabolic disturbances.

Methods: We prospectively followed for up to 10.5 years (mean 4.1 years) a total of 1742 hypertensive patients without cardiovascular disease (55% men; blood pressure [BP] 154/95 mm Hg; age 50 +/- 12 years). A modified National Cholesterol Education Program definition for metabolic syndrome was used, with body mass index in place of waist circumference.

Results: During follow-up, 162 patients developed cardiovascular events (2.28 events/100 patient-years). Event rates in the groups with one to five characteristics of the metabolic syndrome were 1.54, 1.96, 2.97, 3.35, and 5.27 per 100 patient-years, respectively (p < 0.001). A total of 593 patients (34%) had the metabolic syndrome. Patients with the syndrome had an almost double cardiovascular event rate than those without (3.23 vs. 1.76 per 100 patient-years, p < 0.001). After adjustment for age, gender, total cholesterol, creatinine, smoking, left ventricular hypertrophy, and 24-h systolic BP, the risk of developing cardiovascular events was still higher in patients with the metabolic syndrome (hazard ratio [HR] 1.73, 95% confidence interval [CI] 1.25 to 2.38). The syndrome was an independent predictor of both cardiac and cerebrovascular events (HRs 1.48 and 2.11, respectively). The adverse prognostic value of the metabolic syndrome was attenuated but still significant among the 1637 patients without diabetes (HR 1.43, 95% CI 1.02 to 2.08).

Conclusions: In hypertensive subjects, the metabolic syndrome amplifies cardiovascular risk associated with high BP, independent of the effect of several traditional cardiovascular risk factors.